[jaym22]

hey guy just wanted to know if cardio in the morning is the best way to go or just whate ever time u wake up like 12:00 pm.should i ditch 8:00 am cardio or can i sleep alittle later and do it when i wake at whatever time?thanxs

[Viperspit]

I guess that depends on what time you go to bed. If you don't get to bed until 3 or 4am, then I'd wait until noon, your body needs rest more.
If you go to bed at 10pm, then get your lazy ass up and do it at 8am.

[StYLe74]

I feel that doing cardio when you wake up on an empty stomach is best no matter what time it is you get up.

[lithium_09]

Originally Posted by StYLe74

I feel that doing cardio when you wake up on an empty stomach is best no matter what time it is you get up.

agreed

[kenney]

i think it is best to do it in the morning, because i've read that your metabolism is at the highest rate around mid-morning

[jaym22]

i was thinking that if u did cardio in the morning on a empty stomach that u would burn more fat throughout the day. thanks! good info!

[Admin]

It depends on intensity. If you keep it at low intensity then its fine. Mod and high intensity will certainly rip through muscle pretty quick.

[Iron Warrior]

You could also do it after weight training and take advantage of GH secretion due to weight training if you don't want to go to the gym twice a day

[Ironslave]

Disagree about empty stomach cardio, its highly catabolic. Time of day will not affect energy expenditure, i would reccomend having a small meal of something like oats and egg whites in the AM, then cardio later.

[Admin]

When intensity is low its not catabolic at all as most studies on FFA oxidation clearly indicate. I've trained several competitors to VERY low bf% successfully this way.

[Admin]

Originally Posted by Ironslave

ime of day will not affect energy expenditure, .

Can you explain this? The physiological effects can be very different depending on fed/starved state according to time of day.

[Ironslave]

Well, i see cardio in a hypoclycemic state leading to increased cortisol (Sotsky 1989) and chronic cortisolemia inhibiting HSL thus being detremental for fat loss. A good full text:
Effects of Cortisol and Growth Hormone on Lipolysis in Human Adipose Tissue -- Ottosson et al. 85 (2): 799 -- Journal of Clinical Endocrinology & Metabolism

I mean the amount of calories burned via exercise will not change depending if you exercise in the morning, afternoon, or night. Preprandial vs postprandial will have distinct effects no doubt, but that wasnt what i was refering to. I also speculate empty stomach cardio may unnecessarily deplete leptin levels. Overall, i just dont see the benefit of empty stomach cardio being much more superior than doing it mid afternoon a few hours after a meal like oats & whey.

[Admin]

Leptin levels drop over weeks at a time do to prolonged conditions and/or genetic factors, not because of 8 hours of sleep. Low intensity cardio has very little to do with a large drop in blood glucose levels so the whole hypoglycemic argument doesnt really apply here. Simply put, 8 hours of sleep doesnt create a catabolic environment given the fact that testosterone and GH output is at its highest during your first REM cycle which coincides with a slowdown in metabolic rate. Catabolic activity is a condition that is brought about over long periods of time, not during sleep. The term is thrown around way too much. There is little chance that sleep plus low intensity cardio will bring about the condition in which gluconeogeneis is increased to the point of muscle tissue degradation. This is why low vs high is important because of the difference in blood glucose as a fuel source.

I don't understand where you are going with this study:

"The in vitro effects of cortisol and GH on basal and stimulated lipolysis in human adipose tissue were studied using a tissue incubation technique. After preincubation for 3 days in control medium containing insulin, adipose tissue pieces were exposed to cortisol for 3 days. "

Yes, GH and cortisol increase HSL activity which increased the breakdown of triglycerides and the opposite is true of insulin. Don't understand the reference here. The condition in the above study isn't remotely what you would experience upon waking up.

The amount of calories will not change but the ratio's in which FFA's are oxidized vs. glucose is very different and the optimal time to oxidize FFA's due to caloric deficit/exercise is either post workout or in the morning. As long as its low intensity it's extremely effective without any muscle loss.